Suspended ceilings are employed today in many structures because they provide an aesthetic presentation while enabling the routing of hardware such as conduits, electrical wiring, etc, in the gap between the suspended ceiling panels and the structural ceiling of the building itself. This gap also provides a convenient “headspace” whereby ceiling panels may be inserted through openings in a ceiling support grid system and manipulated into an orientation whereby the panels may be lowered onto supporting flanges within the grid system that provide shelves or ledges onto which the edges of the ceiling panels may rest.
According to one mode of construction, the support grid for a suspended ceiling relies on the use of longitudinally extending strips or “runners” that are generally of an inverted “T”-shape in cross-section, having outwardly protruding lateral flanges which provide the ledges upon which the ceiling panels rest. In this type of existing system suspension wires or other connectors descend from the ceiling proper, through the headspace, to connect with the ceiling runners.
In conventional suspended ceiling systems having substantial headspace, the procedure for installing or removing a ceiling panel is to lift the ceiling panel clear of the grid support structure, turn it somewhat in the headspace, and then maneuver it down through the opening within the grid structure. The headspace required for lifting and maneuvering a ceiling panel in order to install or remove it is at least several inches and may, in some cases, take-up considerably more space.
However, in many cases provision of adequate headroom is impractical due to the relatively low height of the structural ceiling. Examples include the basements of homes where even the loss of a few inches in vertical height can give the impression that the ceiling is oppressively low. A need exists for a low headroom suspension ceiling support system that will permit tiles to be installed in place without reliance on the presence of headroom.
It is known to provide support for a drop ceiling through the use of resilient ceiling clips, resilient clamps or clamps. Examples of this type of construction are described in the following U.S. Pat. Nos. 2,059,483; 2,229,064; 3,228,163; 3,969,865; 4,549,375; 5,768,843 and 6,205,732. An advantage of using resilient mounting clamps is that ceiling panels can be placed in position without the necessity of manipulating them in a headspace provided above the gridwork system. This is advantageous when it is desired to keep the drop of the suspended ceiling at a minimum. Using resilient mounting clamps, ceiling tiles can be installed very nearly directly adjacent to the structural ceiling itself.
Retention systems for supporting the grid network of a suspended ceiling can be resilient, permitting the nondestructive disassembly of components by the application of a sufficient disengagement force. They may also be nonreversible, or not readily reversible in that they employ engagement mechanisms that may permit “snap-in” assembly procedures, but disassembly cannot be readily affected without risking the deformation of the engagement elements of the grid support system. Examples in this latter category are U.S. Pat. Nos. 3,784,184 and 4,720,946.
A specific example of a prior art reference addressing these requirements through use of resilient means is found in U.S. Pat. No. 3,263,388 to Bogert. This document discloses a system of interfitting runners and resilient clamps, the clamps being fastened to the structural ceiling itself. The clamps are provided with a serrated grasping face which engages a corresponding serrated face on an upwardly directed flange that forms the stem or leg portion of the inverted T-shaped cross-section for this member. Employing the Bogert system, ceiling panels are placed in position with their peripheral edges resting on the ledges provided by the lateral flanges of the runners. When the upwardly directed stem portion is pressed into the reception slot of the resilient clamps, the ceiling panels are carried along with the runners into their final position. A disadvantage of this system is that the ceiling tiles and runners must both be manipulated simultaneously. For a person standing on ladder or scaffolding, this requirement complicates the procedure of installing ceiling panel.
A need exists for a convenient support system for a suspended ceiling that can be readily installed and which permits the easy removal of the ceiling panels for replacement or access to the headspace behind such panels. It is an object of this invention to address such requirements.
The invention in its general form will first be described, and then its implementation in terms of specific embodiments will be detailed with reference to the drawings following hereafter. These embodiments are intended to demonstrate the principle of the invention, and the manner of its implementation. The invention in its broadest and more specific forms will then be further described, and defined, in each of the individual claims which conclude this Specification.